In truth, the term “Earthlike” is a stretch.

事实上，“类地”这个术语有点夸大。

It joins two other Earthlike planets-Gliese 581d and HD 85512 b-discovered by another instrument within the past few years.

“开普勒22b”加入了几年前刚发现的另外两颗类地行星的行列，即“葛利斯581d”和“HD 85512 b”。

You're probably going to need a rather specific and earthlike planet.

你可能需要一个相当具体的类地行星。

There's an old concept in science fiction called terraforming: going to uninhabitable alien planet and engineering it to be more Earthlike.

在科幻小说中有一个老梗，即“地球化”：去一个不适合居住的外星星球，把它改造得更像地球。

Kepler's biggest quarry was Earthlike planets at just the right distance around their stars for liquid water to exist on their surfaces.

开普勒的最大猎物群是类地行星，它们与其恒星距离适当，这样液态水才能在它们的表面存在。

And among these planets, on the order of a few percent are earthlike enough that we would consider them potentially living planets.

在这些行星中，有百分之几的数量级足够像地球， 以至于我们认为它们可能是有生命的行星。

If only a few of Kepler's possible Earthlike planets turn out to be real, that third number is likely to be in the millions.

如果“开普勒”发现的可能类地行星中有那么几颗可以被证明符合人类居住的条件，那么其他同样符合条件的星球可能有成千上万之多。

On December 5th the scientists in charge of Kepler, a space telescope designed to look for such planets, confirmed their instrument's discovery of its first Earthlike world.

“开普勒”天文望远镜就是为了寻找这类行星而设计的。12月5日，负责寻找工作的科学家们利用“开普勒”发现了第一颗地球类行星。

Extrapolating from these results, they think that an orbiting zone plate measuring somewhere between 15 metres and 40 metres across will be enough to distinguish the spectrum of an Earthlike planet at a distance of 30 light-years.

从这些结果推测，他们认为，一个直径在15到40米、并且在轨道上运行的波带片足够在30光年以外的距离分辨一个与地球相似的行星的光谱。